The euro zone slipped deeper into recession in the last three months of 2012 after its largest economies, Germany and France, shrank markedly at the end of the year.
It marked the currency bloc's first full year in which no quarter produced growth, extending back to 1995.
Economic output in the 17-country region fell by 0.6 percent in the fourth quarter, the EU's statistics office Eurostat said on Thursday, following a 0.1 percent drop in output in the third quarter.
The drop was the steepest since the first quarter of 2009 and more severe than the average forecast of a 0.4 percent drop in a Reuters poll of 61 economists.
For the year as a whole, gross domestic product (GDP) fell by 0.5 percent.
Within the zone, only Estonia and Slovakia grew in the last quarter of the year, although there are no figures available yet for Ireland, Greece, Luxembourg, Malta and Slovenia.
The big economies set the tone.
Germany contracted by 0.6 percent on the quarter, official data showed, marking its worst performance since the global financial crisis was raging in 2009.
France's 0.3 percent fall was also slightly worse than expectations.
Worryingly for Berlin, it was export performance - the motor of its economy - that did most of the damage although economists expect it to bounce back quickly.
"In the final quarter of 2012 exports of goods declined significantly more than imports of goods," the German Statistics Office said in a statement.
The euro hit a session low against the dollar after the weaker than forecast German reading and dropped again after the release of full euro zone figures.
Back revisions to the French figures showed its output fell by 0.1 percent in each of the first and second quarters of 2012, meaning the country has already experienced one bout of recession in the last twelve months.
While the European Central Bank's pledge to do whatever it takes to save the euro has taken the heat out of the bloc's debt crisis, even its stronger members are gripped by an economic malaise that could push debt-cutting drives off track.
French Prime Minister Jean-Marc Ayrault acknowledged for the first time on Wednesday that weak growth was putting his government's deficit goal for 2013 out of reach.
Economists say the euro zone may also shrink in the first quarter of 2013 although more resilient Germany is expected to rebound.
"The chances that the (German) economy will return to growth at the beginning of this year are very good. The early indicators are all pointing upwards," said Andrea Rees, chief German economist at UniCredit.
"The question is how strong the first quarter will be. We expect growth of 0.3 percent but it could be more."
Dutch GDP dropped 0.2 percent over the quarter, keeping it in recession, while the Austrian economy shrank at the same rate.
For the more embattled members of the currency bloc, matters are of course worse.
Italy suffered its sixth successive quarterly fall in GDP - this time by a sharp 0.9 percent - putting it into a longer slump than it suffered in 2008/2009.
Its recession has been deepened by austerity measures that outgoing Prime Minister Mario Monti introduced to stave off a debt crisis.
With an election due on February 24/25, all sides in a three-way race between Monti's centrist bloc, Pier Luigi Bersani's center-left coalition and Silvio Berlusconi's center-right are pledging to cut taxes to try to kickstart economic growth.
Spain, the euro zone's fourth largest economy, released figures two weeks ago which showed it remained deep in recession after a 0.7 percent contraction in the fourth quarter.
Madrid is also pressing on with harsh austerity measures to cut its debt but may be given more time to meet its deficit targets by the European Commission if its economy worsens further.
There are signs that countries like Spain are starting to benefit from harsh internal devaluations - marked by wage falls and job losses aimed at making companies leaner and more productive.
The ECB predicts the euro zone will pick up later in the year although its currency, if it keeps strengthening, could quickly snuff out any of those hard-won competitive advantages for its high debt members.
More recent data for January have already suggested some upturn in the first months of 2013, in the bloc's stronger members at least, and if improvement comes it is likely to be seen in Germany first.
"The debt crisis has ebbed significantly and the global economy has turned up," said Joerg Kraemer at Commerzbank. "Therefore all the important early indicators for Germany are pointing upwards. I expect noticeable economic growth again in the first quarter."
(Additional reporting by Steve Schere, writing by Mike Peacock, editing by Jeremy Gaunt)